1. Field of the Invention
The present invention relates to a pixel structure, and more particularly to a design of a common line in a pixel structure.
2. Description of Related Art
Nowadays, multimedia technologies have been well developed, which mostly benefits from an advancement of semiconductor devices and display apparatuses. Among displays, thin film transistor liquid crystal displays (TFT-LCDs) characterized by high definition, high space effectiveness, low power consumption and no radiation have gradually become mainstream products in the display market. In general, the TFT-LCD mainly includes an active device array substrate, a color filter substrate, and a liquid crystal layer sandwiched between the two substrates. The active device array substrate has a plurality of pixel structures.
FIG. 1 is a top view of a conventional pixel structure. Referring to FIG. 1, a conventional pixel structure 100 includes a substrate 110, a scan line 120, a data line 130, a common line 140, a TFT 150, and a pixel electrode 160. The TFT 150 disposed on the substrate 110 can be electrically connected to the scan line 120 and the data line 130. Practically, the TFT 150 can be turned on by a switch signal transmitted through the scan line 120. After the TFT 150 is turned on, a display signal is transmitted to the pixel electrode 160 electrically connected to the TFT 150 through the data line 130.
Note that light leakage easily occurs in an area A near the common line 140 because of a defective rubbing process. In detail, a film layer covering the common line 140 is relatively protrusive due to the common line 140 disposed underneath, and an extending direction of the common line 140 is rather different from a rubbing direction R in an alignment process. Thus, the rubbing process performed on the area A along the rubbing direction R with use of bristles (not shown) for alignment is not prone to be carried out in an effective manner, such that the area A cannot be rubbed well. As such, there is a great need to resolve issues regarding light leakage and reduction of contrast occurring in the conventional pixel structure 100.